The disclosure relates to a valve, in particular a flow control valve.
Basically, flow valves are valves which serve to regulate the flow rate of a fluid that is used. A butterfly valve as a subassembly of a flow valve is an adjustable constriction in the line flow, which constriction is brought about by the valve. As a result of the hereby increasing flow resistance, the volumetric flow rate changes as a function of the pressure gradient which becomes established via the valve. Unlike the abovementioned butterfly valve, a flow control valve as a further subassembly of a flow valve is additionally equipped with a pressure compensation. As a result, even if a pressure gradient established via the valve changes, a set volumetric flow rate remains unaltered, i.e. the volumetric flow rate is independent of the pressure gradient currently available at the valve. In more concrete terms, this is basically achieved by assigning to an adjustable measuring orifice a pressure regulator, which is acted upon by a spring force, as well as in the opening direction by a pressure prevailing downstream of the measuring orifice and in the closing direction by a pressure prevailing upstream of the measuring orifice. This pressure regulator can here be connected in principle directly upstream or downstream of the variable measuring orifice, and can also be integrated in the measuring orifice.
A flow control valve of this generic type is known from the prior art, for example according to U.S. Pat. No. 6,966,329 B2.
This concerns a proportional pilot-operated flow control valve having a housing in which a hollow compensating piston is arranged in an axially displaceable manner. In the compensating piston is mounted a metering-guide component, a control piston being arranged so as to be able to slide within the guide component. At an axial distance from the metering-guide component, there is also slidably provided within the compensating piston a damping-guide element, which forms a damper chamber in the compensating piston. Inserted in the damper chamber is a biasing spring, which biases the damping-guide element in one direction so as to make contact with the end face of the metering-guide component and which biases the compensating piston in an opposite direction so as to make contact with the end face of the housing. Inserted in the hollow control piston is a control spring, which forces the end face of the control piston against the damping-guide element. Finally a cartridge housing is provided, in which a pilot valve assembly is housed and which is fitted to the valve housing via an adapter.
Although, according to this prior art, the axial motion of the control piston is basically damped by the damping-guide element, the entire valve construction proves to be extremely complex and thus prone to faults, particularly in the small signal range.